Add libdrm to mainline_system

Used by things on /product.

Bug: 130023865
Test: make
Change-Id: I564c6d823ac7e04d6a41dfd1ceb7074755b0bfd8
diff --git a/target/product/mainline_system.mk b/target/product/mainline_system.mk
index ecd5691..d75809c 100644
--- a/target/product/mainline_system.mk
+++ b/target/product/mainline_system.mk
@@ -76,6 +76,7 @@
     android.hardware.secure_element@1.0 \
     android.hardware.wifi@1.0 \
     libaudio-resampler \
+    libdrm \
     liblogwrap \
     liblz4 \
     libminui \